SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0c63e9b4ae0f5541f316087a2ee45a8a1708e1eb961fd2b9bcebb08afc8e520f' 
  AND token = 'p4yfxVQd40cSWlf18d6Mw/r/tWVUesmljqZ3nrKaW14=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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