SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '82bb60843a7c05fb58ba4f175dfd6fdddbceab0b3ba0cbd0db08a64ee08613ad' 
  AND token = 'KtppieJR4chRwsKkkmHxDV7+sLDyY8c2Otw7n5XMzfY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}