SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '867d1998c9830ddd1e84c6e551faf933502f2abb3c5f780d8ca92a06b4ccd648' 
  AND token = '0M7pk+nGF/GKBjXu+lNROED2uwYiPCPbm8umXRyqdHU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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