SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7c560b8c473664c1ac239289fbb14fbc8f0596ee5f947e7721206ff146d30aae' 
  AND token = 'VCWlalgmH1V5UqbWEaN5OJurvuV/UlQmZC9T1YioKXU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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