SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'b11670fac9472c154da2e26b02c1c4dc7cbb25d6c3d626adab56df31fca569ec' 
  AND token = '0SI7gMOraR2l3d4XGQNioaxMIRZYB7EZMERpDX4BtJ4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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