SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a87f9a31f91c0f11bee9c8cc92795e5a5ce45b83166414f1825f42f9c88b1cd1' 
  AND token = 'f6+WtQYPe2ehvDsZZVIQllcZOHAXn2OVDgPM7S25n7I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}