SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2ef15a67aa70390e877e4f9c085646aac2431082b3cc3c37ab6eb7267db94875' 
  AND token = 'OUNIVKARQ+8ALx/yOKDQnsZZ+guK7OXflcqjWpl2DYs=' 
  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"
    }
  }
}