SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '112b8117dd15b226ba9c78aaceedabc9ee33bd547a734830f0325591daa5da45' 
  AND token = 'vgKsGKTEgM540qhCmAUY763zpg0T26NHfh4PQpyXgeE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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