SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c0a002cf987b98c734e13bea026a73027e31d4041fd487076eea653cab8bd957' 
  AND token = '4RfCVDOPtVJiydO8UCr1ldj6M8RHL/l2hNT/cdFpFM4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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