SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6d0e973fc752420d9b13a17f6059a05f8cc4b8ce6da484b50128ea5ceb37d76c' 
  AND token = 'GEds8x2Nk8ErDcV/e816gLSBYxqky2zsRGagJW9EGQU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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