SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '98df2572846b44729387f39ecf968847a5a82637e02e219a0bb044cfdd127d3e' 
  AND token = 'qaLO56TGupw8FpfpCMNQAIbX2okwCnHYbB0Pj4y3nGs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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