SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '618da6a52c58e68a52dc553fa766fa3b5c91827eaf8d84a14cfaa42746059c7e' 
  AND token = 'UHcuBLnikA4PSOZ4wRnCaRqsGqL/a2h33pnciWu+WLY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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