SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e5226cd5b1d508ce4dcdff58159ac734a6143909d1ff1ec0a32f23a92c8faabd' 
  AND token = 'ZJVXTIS0IjPragfXJaQEettzQK73omBFl5seJGPPS0E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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