Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '81756422548f6c52c06b89c651d5ee366f1a29ee1cf086185171c6bbd7410299' 
  AND token = 'ulpMT0bM5ZcS4MMPUGefrLMVamYZ04FKkxXrgSUDePY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}