SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '05668724862e46bfcc85933d6762bca42cbe23abb747161d03132b41dc385363' 
  AND token = '6r0upAQXvduC1NL0WK0uYiRSkCCMqJU4lQpqUWZ87Y4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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