SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '30147ac90a1a06fd58a7042e41c23f7b0ba53c891770b82abc448754b7414465' 
  AND token = 'AiGQMerbyu3iJOX2RKT6S1hImVQwNjr5c4KwFfcVU34=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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