SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd8d89c3701b6372d65aaf3c4e0adf853b490b70bdf6b79f684f1d26931fedabe' 
  AND token = 'JhIYKphYBmRbVUPHgzHWXUearSUUYVfFlozRCkUS8hk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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