SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '618dc96d9182832214c3c00df8cf88e4a59a936caa572c1313d0af4fb9b3834c' 
  AND token = 'jTvdVB/F5KGPJczaM59CqB6rSMu6VVKjYUPJn+OyNzg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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