SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e76daae0424f42e06036063c7a7e829dac9dab9370b4f2f183ff1bacb8d7f2ba' 
  AND token = 'qtA06PUBYo6PNsXiSY4tg+lyioXcrSOLxOs40E1vY4c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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