SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '11c7e9ce7ffb8bd9d12e2a7bb7d37939aca49c1ff08b39b2fb94ceae45f84724' 
  AND token = '/s6qmGvLDeSP3FzmRUWSAX1i6uA1CY24xVGgdPUHTIo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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