SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8f8e8dee419be095f7392793221e72d72d6065d3a3c2a7375e570a5ace6fa095' 
  AND token = 'IbMd/ulB2+qXq/Fq2/8fIGiPU6+/soaOyDCqmoOt4ME=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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