SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'afa37373c92d631d086443e63598cab0d5f3c109fb104d8cfc49765d52eecde0' 
  AND token = 'HmXh+ToUxGCP/CbymfRU6nJYRh7GqYFMAlWovEdwwTE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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