SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd666ee441bb32c10a1a2100b38925b4c68cf2a8bf4e995efdc598ec6958ce3c4' 
  AND token = 'vb0Ggc/iyRiqGV9bCrSSsebMzp8Y1F38E6/yme+F+30=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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