SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '79aa5d4441ecb4dd8cb47c6ffe5bf9e512fe483d71b5676ebbc050a345ecacee' 
  AND token = 'G72qNXJyKtb8oKMZtBGCRrS44Tu2VlEDSZrXcRcuqcY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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