SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'f1461180848dd06be36ed1d5199561d29ed006ba4c36f2a606b63347459e0461' 
  AND token = 'jG6As9klWsTvIXVBNRXhoIT6ZHNYkYqlrDVsxEOorOw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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