SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1ee3fa4278e88770837c72b704c896437df8221a4609f978c2d24c1674869a02' 
  AND token = 'GTPGsYXFCVHGwu0JpGEPGxBDZ3I75bdhf41C8rIAdpQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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