SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9eca879f7a17fca54474496cbd0586a3eb3d96e60841a0d090414f22ca404888' 
  AND token = 'Xlt4mnGRr+/oo26l6dKd1cpf3Ms8nKMcWNNIIRJ3WG8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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