SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '039480edb14e2c7b5f05c5540f0b816bf42fad7cc654bf8c19f073a56b7581b8' 
  AND token = 'ZYEnjiBnq8wvam0qeYKREdfMaQkLf/QU+TIQhNAUzyg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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