SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a0380a9b51d22f7588d8baa844e951aaaef79e11ec867266268e5b763df72adc' 
  AND token = 'MhLtduaDwqbQJwCpK/kB0g/C4+lx0rGgYB48infVZVw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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