SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7964c7778e061a2c3a2e14d3be28bdeffc71b510ecdcfa4e0be383f626c4e180' 
  AND token = 'KF61ElforuQ7edWGXYM1RtGaU/goJf77Hc1xzbmSQGU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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