SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7b965cf913f07d2135161659cef7d01f53035d6d15ebfa432751ede78eaeaa71' 
  AND token = 'gkUF2UuzsCbzenLNt/IrKwvRb3RF2wVAgiamPd24kLk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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