SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b3a6a05ea4e8425a3d646e65f5a623be4ead2fc493be0977ec7043a4ed91b41a' 
  AND token = 'RmenqsmAGj82/s2H41N+ZuJl8EPjVY/f0Dp+EK1zueU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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