SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'adc0720a102cef4af1411357e63efada5c4df7767cdb16825727aaff5dac0994' 
  AND token = 'zWqQpFGayyXbYZCKA66DQR58dly6xrZ+XGxfZQHW/XQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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