SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b5638c95c12b697bd83cb259df3a58024c1b77f5db5240cc9d0074f8af6846e1' 
  AND token = '0gsZCB7/PzkT/961CdbC9HHagdJOJmpIJrEzABs/7bw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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