SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fc0d853fceb2620a23675d5219a91432c96e49ea3de79b19f9a59a4db76b169b' 
  AND token = 'SvBKwDOkoD9g2iifry8mSpXhKywipA0vHWAvqemDZ8o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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