SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f185bf03914278b98f56d4d20ba79b92dd1c0f450f4f532c2f108fa4cf685c99' 
  AND token = 'RvTaL6L7GdQfxRmnQGn7tJtxHy8onW0IzRVmCkrHOVA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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