SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e22aa15049634509dcfcf90b5909645f7242a183066e5925f9b504eabbe648d4' 
  AND token = '0XWjGoKDqjJOcIDnAXIDvlaXD/2MMeKOlkjZV4muYxk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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