SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9f58ebe081f9500ae9755cdca6c1774053156e19a9d62c1ef392148ee3f6ad41' 
  AND token = 'mftpLLVvDsIG/nkzgBhp1Hooz/OsKjvwnbFjS71DHJc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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