SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '02255eaa51679890cfcb594fb4dd7867f91eadb81e588beab62bf1bef4fd8926' 
  AND token = 'lMXqrGsC//7pT0oZxnHyUFXQvyFLYVXpc8KOR894rvo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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