SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6aa6229f030abf5f84b42c7700f0508c217c642d1a18917e8e954c85e7eb05ff' 
  AND token = 'nyIllMstBEoWp4KleEAlLghQ8AMstj6JwSKpk9ktipY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}