SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5995c9c0427e3012957edc0913020c20ae4ee7be73b268293e201b0979c4fe92' 
  AND token = 'esJhU8LA5GHzKAeQ48Laqc1Un5F0LK7Uz/RhVWA+QrQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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