SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bb6df2de353ce6ec84db96bedd39213d85decd40c5d4d5c716d18a66bf46be5c' 
  AND token = 'wIx2cfy171SSNg7HO8Q3eMQwr2yqyOznqFNTpM/aD3U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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