SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '60913bed41cca6b45c78ed7addb7e77297b79078eddb691bfb5210c0b42c1729' 
  AND token = 'MhkiXV27FjJ9co0hdUvTmX2RSlueaUV5AgBS0BNU+aU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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