SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b028c14341803afc8f0d566fd3832ed2e32e894b86f7160a1994e6d653767ac7' 
  AND token = 'Ppntk4s6MFsArorC41amWA0vqd88jv12wsreQysbZUA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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