SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6316bd91f95dc7f4946b2eb754c8533c0d9fbb69d385a6f3236261d0aed0376b' 
  AND token = 'o10gqr04wRnXXR5oVhJyLd/MJBHC26HTvECWmi01hLc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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