SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ea0c1cfebe364c978c5376f1b22a665e1d84d5653f09379df21b3736ad8f6cd9' 
  AND token = 'OTwM61zYW3UiQT2ND0/ZSu23v/ANkobVbcY313WTgg4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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