Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4d55f754201745c550e035fcd263bdbef3c2649cf3642abbbf036536adf14579' 
  AND token = '3DJQdEHUUqbzEKtXH4GkCYxp00PBiLaHYF7rRDjEskc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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