SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9ca71e75ef1e63da6130885b73d9fe286697f91f0ff591e1202238f336ace05d' 
  AND token = 'wqSztOsL6KY2qGacfYZv7ko11woqjtZslRUGNwWaQYY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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