SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '83cd2392464ddb2ac88156e99b1ead7294fab9622bdc1a15007611f6913d0c6f' 
  AND token = 'Avasbl8yz3ORSe+LRiIn+mXl25U08sWX4K+aP0uSRqc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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