SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '810c95ca1854bdb27cc19a02bf76c3113332a85727831cc5addbfd28be3956d7' 
  AND token = 'pnPWrDByW47VFBCMIemXLy/wtDZTVzh7YlQKQebBN5k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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