SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2803cf6780622356cca510fbd0cd31f3fe8f5da73179df508c6731e90fda8ffe' 
  AND token = 'Y7CK9DDFyWWRBbv+B62RTBqVoAIqYjqH3VozxbUKc8g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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