SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '20b0edb368a2abb1ca84432506974bcc161229d9f5af7a6811ef9d067e658138' 
  AND token = 'Jia0SgCaZiYfVxPohKlUaTM/JmU647ICoOLBzpxSu20=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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