SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7385a877378c18a1bd8577492abb757da33202d665a036b2c59b7b0c953f2ef7' 
  AND token = 'ZazF6GLQ+ZHqiv+GlvOR09Rmg/ejyFHUMbv9ZF1yoR8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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