SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0883e3819f40cc658e74a9ad488cec61f719a025a9826500f6a359bf87fab32f' 
  AND token = '+MVjkESdJSYR/AG4sw9IAXJosWrJHU1uVYGdbxqPVbg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00079

JSON explain

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