SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5692344989eeea58f8ff7e534d4e3f205ab8f5e47aca1a3f634f0dccee4ac587' 
  AND token = 'TEvLplQat87m+Vj4/DGF8gyKq7qokkwhFlkb1+yeJzE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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