SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '41ae990927ba0c281af324298243812647204c3de3fb8effc47547e5be95a675' 
  AND token = 'B/3UQQsFgyR9HDzn3VAK/ip7hic2FACMTQYZSYek1GY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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