SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4c97d4dc3438f11b370ef7a4d586febf450672e80cc2cad5acd2051632e8aa80' 
  AND token = '8a0T0kW+wkAZOK/C+JdkuP+TyYkPgW+bKpHz8X5rxII=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00102

JSON explain

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