SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a917835de77086a64fce8bc2acb9387343f76145e8d31dd458018d23b764a1eb' 
  AND token = 'SEECLWbRZojjgKFDUZi77LZQryo6M211A4c1EuTzDFg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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