SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4eba847f2980d9a7776a81fc83330320ab32bebff10a0c9881d1e9a6f6fff144' 
  AND token = 'psy8zFREdBucQDkbulJVZvLAZTeA3jPaYGB6Db+HIPU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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