SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '19431a7003be6c89b66de2e3b42d7895619c3f38a16eabb4e5e989ff34af5fdd' 
  AND token = 'lHcA/NzlXp8bGdaVCjUjQcNyg/micbwZO7azAP53+qE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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