SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6cd93971afb4f1f37c1fea89318b6fd94f5c67ae0cd6b14e1b0f4bfdfd930921' 
  AND token = 'Ad+kYmvRugNJ8U5cnJpk5VVFqKgZW/V/LvlzfFRgwlU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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