SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '41ca52479364a119887bfec5b5bdf3ee9b34a1262f90d5269c19f0ddb6612325' 
  AND token = 'I69VAnmB7FktJh3Crt1mtfitDOHrMpKiIUeVo4aJW9c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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