SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a3d02df2c72e39c3f4f8804cc1ccc00f5295316285ad44458f25ffa5f0101bbb' 
  AND token = 'syvdi2QzUbfgIBgRQTAOFM7/8F1KxpVQBjs18YSAwas=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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