SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cab12bdcb714d6497841c9762d67aad073c1407ef41b069e5499d3fcf5c8289b' 
  AND token = '5jya4/O8F2yQsdONCOSQ0XcAa/Bntqa/A4DTOnsy8Vw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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