SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '491d4dd9ef9f3764439b3204942eaa88a4eed90091ee4b7a172bbe2dd46b5c1a' 
  AND token = 'CyHhNNBCOIBP2YGtjdUKndzU/hBY7TdiW7Mn1B7vp6U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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