SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b0728592d080c8025382a8c65d7b41ef70efaf5decfe96cc7c310fb413134d96' 
  AND token = 'IzcIluktvrQjJszk/lwtWtnrsErcwhomMHj0OydyR14=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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