SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dbd839c4ee2b2e66b4cee044589cda14a88058bef5ec707557196723315c49d0' 
  AND token = 'IEpuv15ODDoFCTY3n+xonFwIASmLP/L/j7plrSZbohM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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