SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7e63751f19cd1527faa63b43eba9f10b5261559b052d2ddd71d8b0e190e003f6' 
  AND token = '1RGzbUDaz21Q6EOig/5w/ngnFFbkPiuM2+GQEygGarE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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