SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '78cd1851542dfbc9f8ef704d27662ee53610fd970f868de7366e19e80a527765' 
  AND token = 'TtRW2cYrzWyDgQl6M2kQKu/sIBm2YZBckfxjgCQwgz8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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