SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '365be15d8142c2c2ede188acd54352ac4e765e93fc74adc11afe6ef64d654ad1' 
  AND token = 'bNFttF1iO1SL9rZ775QNp4Qznfv+QojfxhwFbh9rWyI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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