SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a755d2919f5aaa544adad11a839013a9706e3237eac870dcf93ec352b4d2ba0b' 
  AND token = 'mvqcpyoSQHy00/i+o//pMAaB/TcqXnZnZiFfaxNu8gc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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