SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '36c0ff1e7fe77da134f9bef6f1fad814e554b1bdba272a1515e431d6c9836ff2' 
  AND token = 'JuxSWF2jV8qZ0cKDnHHkAnMNuaAyIS2MdSb/4U+U5QE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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